JP3433745B2 - Manufacturing method and manufacturing apparatus for three-dimensional shaped object - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional shaped article manufacturing method and apparatus for producing a three-dimensional shaped article by sintering and curing a powder material with a light beam.

[0002]

2. Description of the Related Art There is a method of manufacturing a three-dimensional shaped object known as a stereolithography method. The manufacturing method disclosed in Japanese Patent No. 2620353 and the like forms a sintered layer by irradiating a predetermined portion of a layer of an inorganic or organic powder material with a light beam to sinter the powder of the portion, By coating a new layer of powder material on the sintered layer and irradiating a predetermined portion of the powder layer with a light beam to sinter the powder at the relevant portion, a new layer is integrated with the lower sintered layer. It is intended to create a powder sintered part (three-dimensional shaped object) in which a plurality of sintered layers are laminated and integrated by repeating the formation of a different sintered layer. Data (CAD data)
Since a light beam is radiated based on the cross-sectional shape data of each layer generated by slicing a model into a desired layer thickness, a three-dimensional shaped object of arbitrary shape can be manufactured without a so-called CAM device. In addition, it is possible to quickly obtain a molded article having a desired shape as compared with a manufacturing method such as cutting.

By the way, unnecessary powder adheres to the periphery of the portion which is sinter-cured by irradiation with a light beam, due to the heat transferred, and the adhered powder forms a low-density surface layer. Formed into a model. In order to remove this low-density surface layer and obtain a three-dimensional shaped object with a smooth surface, the applicant of the present invention has disclosed that in Japanese Patent Application No. 2000-306546.
It has been proposed to insert a step of removing the surface portion and / or unnecessary portion of the modeled object produced up to that time after forming the sintered layer into the steps of forming the sintered layer a plurality of times. In this case, by repeatedly forming the sintered layer and removing the surface portion and / or unnecessary portions of the modeled object, the surface can be finished without being restricted by the drill length or the like.

[0004]

However, when the above removing step is inserted, the following new problem arises. That is,
As shown in FIG. 8, an inorganic or organic powder material is supplied to the surface of the modeling base 22 on the upper surface of the elevating table 20 and smoothed by the blade 21 to form the first powder layer 10, and the powder layer 10 is formed. The light beam (laser) L is radiated to the portion of the base 22 to be hardened to sinter the powder, and the base 22
After forming the sintered layer 11 integrated with
0 is lowered a little (Δt1), the inorganic or organic powder material is supplied again, and is smoothed by the blade 21 to form the second powder layer 10, and the light beam ( Laser) L to sinter the powder to form the sintered layer 11 integrated with the lower sintered layer 11 is repeated a plurality of times, and the total thickness of the sintered layer 11 is, for example, a removing means. When the required value obtained from the tool length of the milling head 41 or the like is reached, the removing means is operated to cut the surface part of the modeled object that has been modeled up to that time so that the high-density part is entirely covered on the surface of the modeled object. When exposed to the surface, a groove 12 is formed around the shaped object (including the inner circumference when the inner circumference is cut) as shown in FIG.

Therefore, the supply of powdered material (see FIG. 10 for example)
As shown in FIG. 3, when the lifting table 20 is lowered by one step, the material supply table 13 in the material tank 15 is raised by one step, and the powder material of the material tank 15 is moved to the modeling tank 25 side by the blade 21 and leveled), it is removed. In the process, since the groove 12 is formed as shown in FIG. 9, immediately after this, the powder material is insufficient due to the existence of the groove 12, and as shown in FIG. 11 cannot be completely covered, which causes defects in the next sintered layer 11. In addition, since the deficiency is accumulated each time the removing process is performed, the defective portion gradually becomes larger, and it becomes impossible to obtain a desired three-dimensional shaped object.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for manufacturing a three-dimensional shaped object and an apparatus therefor capable of surely obtaining an object having a smooth surface. To provide.

[0007]

SUMMARY OF THE INVENTION In the method for producing a three-dimensional shaped object according to the present invention, however, a layer of inorganic or organic powder material is irradiated with a light beam at a predetermined position to sinter the powder at that position. To form a sintered layer, coat a new layer of powder material on this sintered layer, and irradiate a light beam at a predetermined location to sinter the powder at that location to sinter the lower layer. Repeatedly forming a new sintered layer that is integrated with the layer to create a powder sintered part in which a plurality of sintered layers are laminated and integrated. The step of removing the surface portion and / or unnecessary portion of the modeled object is inserted into the steps of forming the sintered layer a plurality of times, and the powder material is supplied immediately after the removal step when forming a new layer of the powder material. Increase the amount from the cutting length when removing
Is calculated and the amount is increased based on the calculation result . Even if a groove is formed around the formed article by the removing step, the groove is filled with the powder material increased in proportion to the shortage, so that the next new powder layer is uniformly formed over the entire surface.

[0008]

The present invention also relates to an inorganic or organic powder.
By irradiating a predetermined position on the layer of powder material with a light beam,
A sintered layer is formed by sintering the powder, and the sintered layer is
A new layer of powdered material on the
By irradiating and sintering the powder at the relevant location, the lower sintered layer
Repeatedly forming a new sintered layer integrated with
To produce a powder-sintered part in which multiple sintered layers are laminated and integrated.
It was created after the sintered layer was formed.
The process of removing the surface part and / or unnecessary parts of the modeled object
It is inserted during the multiple steps of creating the sintered layer and
Powder for forming a new layer of powder material immediately after the removal process
The supply amount of powder material was calculated from the cutting length at the time of removal.
The number of repetitions of the powder material determined based on the increment
With other features in repeated dosing of the feed coating
There is.

The present invention also relates to an inorganic or organic powder.
By irradiating a predetermined position on the layer of powder material with a light beam,
A sintered layer is formed by sintering the powder, and the sintered layer is
A new layer of powdered material on the
By irradiating and sintering the powder at the relevant location, the lower sintered layer
Repeatedly forming a new sintered layer integrated with
To produce a powder-sintered part in which multiple sintered layers are laminated and integrated.
It was created after the sintered layer was formed.
The process of removing the surface part and / or unnecessary parts of the modeled object
It is inserted during the multiple steps of creating the sintered layer and
Powder for forming a new layer of powder material immediately after the removal process
Monitoring the powder material supply amount by monitoring the surface condition of the powder layer
The number of repetitions of the powder material determined based on the results
With other features in repeated dosing of the feed coating
There is.

Further, the apparatus for producing a three-dimensional shaped object according to the present invention corresponds to a powder layer forming means for forming a layer of an inorganic or organic powder material, and irradiating a predetermined portion of the powder layer with a light beam. Sintered layer forming means for sintering powder at a certain location to form a sintered layer, and adjusting means for adjusting the relative distance between the sintered layer forming means and the sintered layer are provided, and the surface portion of the modeled object and or a removal means for removing unnecessary portions, to have <br/> features of the surface state of the powder layer on the basis of to the monitoring results monitored and a monitoring means for controlling the supply of powdered material There is.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below based on an example of an embodiment. FIG. 2 shows a three-dimensional shaped object manufacturing apparatus according to the present invention. A powder layer forming means 2 for forming a powder layer 10 having a predetermined thickness Δt1 by smoothing an inorganic or organic powder material supplied onto an elevating table 20 which moves up and down in a closed space with a squeegee blade 21, and a laser. The sintered layer forming means 3 for sintering the powder to form the sintered layer 11 by irradiating the powder layer 10 with the laser output from the oscillator 30 via the scanning optical system such as the galvano mirror 31 is provided. A removing means 4 in which a milling head 41 is provided on the base portion of the powder layer forming means 2 via an XY drive mechanism (preferably a linear motion linear motor drive in terms of speedup) 40. It is provided.

In the production of the three-dimensional shaped object in this one, as in the conventional example, as shown in FIG. 8, it is an adjusting means for adjusting the relative distance between the sintered layer forming means 3 and the sintered layer. The powder layer 10 of the first layer is formed by supplying an inorganic or organic powder material to the surface of the molding base 22 on the upper surface of the elevating table 20 and smoothing it with the blade 21. The powder is sintered by irradiating with a light beam (laser) L to form the sintered layer 11 integrated with the base 22.

After that, the elevating table 20 is lowered a little and the inorganic or organic powder material is again supplied to the blade 2
The second powder layer 10 is formed by smoothing with 1, and a light beam (laser) is applied to the portion of the powder layer 10 to be cured.
L is irradiated to sinter the powder to form the sintered layer 11 integrated with the lower sintered layer 11. The elevating table 20 is lowered to form a new powder layer 10, and the light beam The target three-dimensional shaped object is manufactured by repeating the step of irradiating with the sintered layer 11 at a required position, and for example, a spherical iron powder having an average particle diameter of about 20 μm as a powder material, A carbon dioxide laser is suitable as the light beam, and a thickness Δt1 of the powder layer 10 is preferably 0.05 mm.

The light beam irradiation path is preliminarily defined by three-dimensional CAD.
Create from data. That is, similarly to the conventional one, the contour shape data of each cross section obtained by slicing the STL data generated from the three-dimensional CAD model at an equal pitch (here, 0.05 mm) is used. At this time, it is preferable to perform irradiation with a light beam so that at least the outermost surface of the three-dimensional shaped object can be sintered so as to have a high density (porosity of 5% or less).

The formation of the powder layer 10 and the irradiation of a light beam to form the sintered layer 11 are repeated, but the total thickness of the sintered layer 11 is, for example, in the removing means 4. When the required value obtained from the tool length of the milling head 41 or the like is reached, the removing means 4 is once operated to cut the surface portion of the modeled object modeled up to that point. For example, the tool (ball end mill) of the milling head 41 has a diameter of 1 mm, an effective blade length of 3 mm and a depth of 3 mm.
If the cutting process is possible and the thickness Δt1 of the powder layer 10 is 0.05 mm, the removing means 4 is operated at the time when the 60 sintered layers 11 are formed.

By the cutting process by the removing means 4, the low-density surface layer formed by the powder adhering to the surface of the modeled object is removed, and at the same time, the high-density part is entirely exposed by cutting into the high-density part. . For this reason, the sintered layer 11 is made slightly larger than the desired shape.

The cutting route by the removing means 4 is created in advance from the three-dimensional CAD data, like the light beam irradiation route. At this time, the contour line machining is applied to determine the machining path, but the Z-direction pitch does not need to be particular about the stacking pitch at the time of sintering, and in the case of a gentle inclination, the Z-direction pitch is made finer and interpolated, A smooth surface may be obtained. For example, when cutting is performed with a ball end mill having a diameter of 1 mm, the cutting depth is 0.1 to 0.5 m.
m, the feed rate is 5 m / min to 50 m / min, and the tool rotation speed is 20,000 rpm to 100,000 rpm. The details of the removing process are described in the above application.

When the removing work by the removing means 4 is performed in this manner, the grooves 12 are formed around the upper portion of the shaped article which is a mass of the sintered layers 11 laminated up to that time, as described above. Immediately after the formation of the next powder layer 10,
The groove 12 is filled by increasing the supply amount of the powder material.
When the supply amount of the powder material is determined by the amount of increase of the material supply table 13, the amount of increase of the powder material is increased by increasing the amount of increase of the supply amount of powder material. As a result, the groove 12 is filled with the powder material as shown in FIG.
A new powder layer 10 can be formed on the entire surface. When the amount of powder material supplied is increased, it is preferable that the moving speed of the blade 21 be slower than the normal moving speed. This is because the groove 12 can be surely filled.

Increasing the amount of powder material supplied may be increased by two steps instead of the normal one step when the rising pitch of the material supply table 13 is fixed, as shown in FIG. The material supply step (the movement of the material supply table 13 and the movement of the blade 21) may be repeated a plurality of times, but if the amount of rise can be controlled in detail, the groove 12 formed in the removal step in the previous stage may be removed. It is preferable to calculate the volume and control the rising amount so that the powder material supply amount can be increased by this volume. The above volume is the path length (cutting length) CL of the tool 44 as shown in FIG.
And tool diameter φ, machining pitch p, cutting depth D of tool 44
Can be calculated from Of course, the number of repetitions of the powder material supply step (or the number of rising steps of the material supply table 13) may be determined according to the volume of the groove 12.

In addition, when the powder layer 10 is formed immediately after the removing step, the surface condition of the powder layer 10 is monitored by the monitoring means 5 as shown in FIG. 5, and if the surface is not flat, the powder material is supplied again. You may do it. For monitoring the surface condition of the powder layer 10, the powder layer 1 irradiated with a laser line light is used.
It is possible to preferably use a laser cutting method in which the surface of No. 0 is imaged in an oblique direction by the camera 50 and the surface state is measured by image processing of this captured image. If it is a plane, it is Fig. 6 (a).
As shown in FIG. 7, the laser line LL becomes a straight line, whereas when the groove 12 is left or the entire surface is not leveled, the laser line LL is a portion of the groove 12 as shown in FIGS. 7B and 7C. The fact that it is a plane is determined by utilizing the fact that it is not connected or it becomes a diagonal line.

In addition, when the removing step is performed by cutting, the powder 1 displaced by the tool 44 as shown in FIG. 7 (a).
Since the particles 6 are scattered around the groove 12, the molding tank 25 is vibrated immediately after the removing step as shown in FIG. 7B, and the powder 16 scattered on the upper surface causes the grooves 12 to spread.
It is also possible to form a new powder layer 10 after burying the powder and leveling the surface. In this case, a vibration exciter 9 (see FIG. 2) that applies vibration to the entire modeling tank 25 equipped with the lifting table 20 may be installed under the control of the control unit of the apparatus for manufacturing a three-dimensional shaped object.

In each of the above examples, the removal of the surface portion of the modeled object has been described, but the removed portion is not limited to the surface portion of the modeled object, and is originally unnecessary for the sake of modeling. If a certain portion also needs to be formed, this unnecessary portion may be removed. Further, although the powder material is supplied from the material tank 15 by the blade 21, the powder material can be supplied in any form as long as the supply amount of the powder material can be increased immediately after the removing step. It may be supplied.

[0024]

As described above, according to the method for producing a three-dimensional shaped object of the present invention, by irradiating a predetermined portion of the layer of the inorganic or organic powder material with a light beam and sintering the powder at the corresponding portion. Forming a sintered layer, coating a new layer of powder material on this sintered layer, irradiating a light beam at a predetermined location to sinter the powder at the relevant location, and integrate it with the lower sintered layer. When forming a powder sintered part in which a plurality of sintered layers are laminated and integrated by repeatedly forming a new sintered layer that has become Since the step of removing the surface part and / or the unnecessary part is inserted into the process of creating the sintered layer multiple times, that is, the creation of the sintered layer and the removal of the surface part and / or the unnecessary part of the shaped object are repeated. In order to finish the surface without being restricted by the drill length etc. Are those that can gel, yet increasing the supply amount of the powder material in the formation of the new layer immediately after the powder material of the removal step, from cutting length upon removal
Since the amount is calculated and the amount is increased based on the calculation result, even if a groove is formed around the modeled object by the removing step, the powder material is insufficient and a defective portion is generated in the next sintered layer. Therefore, it is possible to reliably obtain a modeled object with a smooth surface , especially from the cutting length during removal.
To calculate the amount to increase and to increase the amount based on the calculation result
In addition, it was possible to increase the required amount, and the increased amount was insufficient.
It is something that is not too much .

[0025]

According to the invention of claim 2, when removing
Repetition determined based on the increment calculated from the cutting length
In order to increase the quantity by repeatedly supplying and coating the powder material a number of times
In addition, there is no defect due to lack of powder,
The amount of increase is insufficient or too much and is wasted.
There is nothing to do.

Further, in the invention of claim 3, the powder layer
The surface condition of the is monitored and determined based on the monitoring result
Increase the amount by repeating the supply and coating of powder material for the number of repetitions
Therefore, the lack of powder does not cause defects.
In addition, it will be wasted because the amount of increase is insufficient or too much.
It is something that does not happen.

[0028]

The apparatus for producing a three-dimensional shaped object according to the present invention comprises a powder layer forming means for forming a layer of an inorganic or organic powder material, and a predetermined portion of the powder layer, which is irradiated with a light beam. And a means for adjusting the relative distance between the sintered layer forming means and the sintered layer, and the surface portion of the modeled object and / or Since the removal means for removing the unnecessary portion and the monitoring means for monitoring the surface condition of the powder layer and controlling the supply of the powder material based on the monitoring result are provided, the removal process can be performed around the modeled object. It is possible to prevent the generation of a defect in the next sintered layer by filling the groove formed in the groove, and it is possible to manufacture a modeled object having a smooth surface and to prevent the powder
You can make up for your shortage .

[0030]

[Brief description of drawings]

FIG. 1 is an operation explanatory diagram according to an example of an embodiment of the present invention.

FIG. 2 is a schematic perspective view of the above.

3A and 3B are explanatory diagrams related to the calculation of the volume of the groove in the above, wherein FIG. 3A is a plan view and FIGS. 3B and 3C are sectional views.

4A and 4B are cross-sectional views of another example.

FIG. 5 is a schematic perspective view of another example.

6 (a), (b) and (c) are diagrams for explaining the above operation.

7A and 7B are cross-sectional views of another example.

FIG. 8 is an explanatory diagram of a basic manufacturing method.

FIG. 9 is a cross-sectional view in the removing process of the above.

FIG. 10 is an explanatory diagram of the above-mentioned powder material supply.

FIG. 11 is a cross-sectional view at the time of supplying the powder material immediately after the removing step in the above.

[Explanation of symbols]

L light beam 4 Removal means 10 powder layer 11 Sintered layer

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Satoshi Abe 1048, Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Works, Ltd. (72) Hirohiko Togeyama, 1048, Kadoma, Kadoma, Osaka Prefecture (72) Inventor Masataka Takenan 1048, Kadoma, Kadoma, Osaka Prefecture, Matsushita Electric Works, Ltd. (72) Inventor, Master Master: Kagami Nagashi, Osaka 1048, Kadoma, Matsushita Electric Works, Ltd. (72) Tokuo Yoshida, Kadoma, Osaka Kadoma 1048, Matsushita Electric Works, Ltd. (56) Reference JP 2000-73108 (JP, A) JP 2002-115004 (JP, A) JP 3010312 (JP, B2) (58) Fields investigated (Int.Cl) . ⁷ , DB name) B29C 67/00 B22F 3/105 B22F 3/16

Claims (4)

(57) [Claims] 1. A sintered layer is formed by irradiating a predetermined portion of an inorganic or organic powder material layer with a light beam to sinter the powder at that portion, and a sintered material layer is formed on the sintered layer. By coating a new layer and irradiating a predetermined location with a light beam to sinter the powder at the relevant location to form a new sintered layer integrated with the lower sintered layer, a plurality of layers are repeatedly formed. When creating a powder-sintered part in which the above-mentioned sintered layers are laminated and integrated, the step of removing the surface part and / or unnecessary parts of the modeled object created up to that time is performed multiple times. The performance is calculated by inserting the powder material into the layer formation process and calculating the increment from the cutting length at the time of removal to calculate the supply amount of the powder material when forming a new layer of powder material immediately after the removal process.
A method of manufacturing a three-dimensional shaped object, which comprises increasing the amount based on a calculation result . 2. A layer of inorganic or organic powder material
Irradiate a light beam on a specified location to sinter the powder at that location.
To form a sintered layer, and the powder material on top of this sintered layer.
Corresponding by coating a new layer and irradiating a light beam on a predetermined place
By sintering the powder in one place, it becomes integrated with the lower sintered layer.
Repeatedly forming a new sintered layer,
For making powder-sintered parts with laminated layers
The surface of the modeled object that has been created so far after the formation of the sintered layer
Parts and / or unnecessary part removal process multiple times
Inserted during the layer creation process and immediately after the removal process
Of powder material for forming new layer of powder material
Based on the increment calculated from the cutting length during removal.
The powder material supply coating is repeated for the number of repetitions determined by
A method for producing a three-dimensional shaped object, which is characterized by returning and increasing the amount . 3. A layer of inorganic or organic powder material
Irradiate a light beam on a specified location to sinter the powder at that location.
To form a sintered layer, and the powder material on top of this sintered layer.
Corresponding by coating a new layer and irradiating a light beam on a predetermined place
By sintering the powder in one place, it becomes integrated with the lower sintered layer.
Repeatedly forming a new sintered layer,
For making powder-sintered parts with laminated layers
The surface of the modeled object that has been created so far after the formation of the sintered layer
Parts and / or unnecessary part removal process multiple times
Inserted during the layer creation process and immediately after the removal process
Of powder material for forming new layer of powder material
The quantity is based on the result of monitoring the surface condition of the powder layer.
The powder material supply coating is repeated for the number of repetitions determined by
A method for producing a three-dimensional shaped object, which is characterized by returning and increasing the amount . 4. A layer of inorganic or organic powder material
The powder layer forming means to be formed and a light is applied to a predetermined portion of the powder layer.
Irradiate a beam to sinter the powder at the relevant location to form a sintered layer.
Of the sintered layer forming means and the sintered layer forming means
With the adjustment means for adjusting the relative distance,
Removal means for removing the surface portion and / or unnecessary portion of the object
And the surface condition of the powder layer is monitored and the powder is based on the monitoring results.
And a monitoring means for controlling the supply of powdered material.
Characteristic three-dimensional shaped object manufacturing equipment .